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A cylindrical tank, 14 m in diameter and 10 m high, is full of water. The tank is standing upright on a flat circular end. How much work is required to pump half the water over the top of the tank? (The density of water is 1000 kg/m³ ). (Use symbolic notation and fractions where needed.)

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The amount of work required to pump half the water over the top of the tank is approximately
$76,995 \mathrm{~J}$ when rounded to the nearest whole number.

The tank is a cylinder with a diameter of
$14 \mathrm{~m}$, so the radius
$(r)$ is
$7 \mathrm{~m}$.

The height
$(h)$ of the tank is
$10 \mathrm{~m}$.

The volume
$(V)$ of the water in the tank is given by the formula
$V = πr^2h$.

Plugging in the values, we get
$V = π(7^2)(10) = 490π \mathrm{~m}^3$.

To find the volume of half the water, we calculate
$V/2 = (490π)/2 = 245π \mathrm{~m}^3$.

The density
$(\rho)$ of water is
$1000 \mathrm{~kg/m^3}$.

The mass
$(m)$ of the water is given by the formula
$m = \rho * V$.

Plugging in the values, we get
$m = 1000 * 245π \mathrm{~kg}$.

The weight
$(W)$ of the water is given by the formula
$W = m * g$, where
$g$ is the gravitational acceleration (
$9.8 \mathrm{~m/s^2}$).

Plugging in the values, we have
$W = (1000 * 245π) * 9.8 \mathrm{~N}$.

The work
$(\mathrm{W})$ done to lift the water over the top of the tank is given by the formula
$W = F * d$, where
$F$ is the force (weight) and
$d$ is the distance (height of the tank).

Plugging in the values, we get
$W = (1000 * 245π) * 9.8 * 10 \mathrm{~J}$.

So, the amount of work required to pump half the water over the top of the tank is
$(1000 * 245π) * 9.8 * 10 \mathrm{~J}$. This can be simplified as
$24,500π \mathrm{~J}$ or approximately
$76,995 \mathrm{~J}$ when rounded to the nearest whole number.

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